Inflammatory bowel disease (IBD) is a group of illnesses, primarily ulcerative colitis or Crohn's disease, that affects the intestines. It has been estimated that over 600,000 Americans suffer from some type of IBD annually. IBD typically causes the intestines to become inflamed. Symptoms of IBD can include abdominal cramps and pain, diarrhea, bleeding, and weight loss.
Ulcerative Colitis (UC) is an inflammation of the lining of the colon and rectum, particularly the mucosa. The disease typically begins in the rectosigmoid area extending proximally through the colon, and may eventually attack the majority of the large bowel resulting in acute and/or chronic inflammation. Acute and chronic inflammation within the colonic mucosa generates inflammatory mediators, called cytokines, which perpetuate the inflammatory process. UC is characterized by flare-ups followed by long periods of remissions. It is a lifelong disease that is estimated to affect as many as two million people in the United States. The major symptoms of ulcerative colitis are bloody diarrhea and abdominal pain, often with fever and weight loss. Additional symptoms of UC include increased stool frequency, rectal bleeding, cramping, weight loss, anemia, intestinal pain, and fever. The clinical course of ulcerative colitis is variable. Victims of UC are also at an increased risk for the development of intestinal cancer. The onset of UC may even cause psychological problems for some people, such as anxiety and depression, while under the strain of this debilitating disease.
Crohn's disease is a chronic disorder that causes inflammation of the digestive or gastrointestinal tract. While not limited to any specific area of the GI tract, it typically affects the end of the small intestine and beginning of the large intestine or colon. UC is generally limited to the colon. Crohn's disease can be difficult to distinguish from UC. Some patients are simply diagnosed with colitis when a specific diagnosis is too difficult. Crohn's disease, like UC, is marked by an abnormal response by the immune system. Unlike UC, Crohn's disease affects more than just the mucosa (superficial layers), Crohn's disease can affect all layers of the intestine, sometimes in a random fashion.
Currently, there is no medical cure for IBD. The available treatments aim at reducing inflammation of the epithelium of the colon, thereby controlling gastrointestinal (GI) symptoms. The major classes of medications used today include aminosalicylates, corticosteroids (e.g., prednisone), and immunomodulatory medicines (e.g., azathioprine and cyclosporine). In view of the deficiency the existing methods of treating ulcerative colitis, it is desirable to develop more effective therapeutic agents.